Optical generation of a spatially variant two-dimensional lattice structure by using a phase only spatial light modulator

摘要

We propose a simple and straightforward method to generate a spatiallyvariant lattice structures by optical interference lithography method. Usingthis method, it is possible to independently vary the orientation and period ofthe two-dimensional lattice. The method consists of two steps which are:numerical synthesis of corresponding phase mask by employing a two-dimensionalintegrated gradient calculations and experimental implementation of synthesizedphase mask by making use of a phase only spatial light modulator in an optical4f Fourier filtering setup. As a working example, we provide the experimentalfabrication of a spatially variant square lattice structure which has thepossibility to guide a Gaussian beam through a 90{\deg} bend by photoniccrystal self-collimation phenomena. The method is digitally reconfigurable, iscompletely scalable and could be extended to other kind of lattices as well.